The sources said that P K Grover, whom Mishra succeeded today on his superannuation, was eligible and, therefore had been appointed by the Speaker sometime back.
Besides, they said that it was not for the first time that anyone outside the Lok Sabha Secretariat had been appointed to the post.
S Gopalan and T K Vishwanathan, who had held the post of Secretary General in the past, were not from within the Secretariat, they said.
Leader of the Congress Mallikarjun Kharge argued that he was not questioning the appointment made by the Speaker, but was only contending that due procedure of consulting the opposition was not followed.
As there is no recognized Leader of the Opposition, she may not have consulted him regarding the appointment, he said.
Kharge also wondered whether no official of the Lok Sabha Secretariat was capable of taking over as the Secretary General.